Whenever I go to load one of my saves it says it requires downloadable content or something like that. Is this fixable??

alot of us have this problem and no it is not fixable at least not by our capabilities we will just have to wait for a patch and hope that it fixes our issues,and if not we will have to start a new game but at least we wont run into this problem again which is bad news for me losing 37 hours but what can we do right.and if you are willing to start a new game try and look into any cheap ways of getting back to where you were at it will give you something to do while we wait.just a thought

I happened to have a save right before I entered Vault 3, but it's a shame because I really wanted to do the Brotherhood quests. Plus it's back like 5 levels.

be cautious because since you have already seen the DLC bug it will happen again with your other save files.i know this because after i encountered the dlc i loaded a earlier save and it worked for about as long as i was playing i loaded the file a few times and no problems then again and bam the DLC bug again so now i have no saves.but i have found alot of great stuff i missed with my first play through of the game so im not as mad that i have to start a new game since i know i can make it better than my last now but i still have to wait for the new patch before i can start.

by the way you said you were back 5 levels if you want to make it faster goto vault 11's sacrificial chamber beat the robots check the maintenance computer and click all the dialogs since i dont remember which one it is but you get like 500 ex for every click so if you want you can just skip to level 30 or use it just to get back to where you where.hope this helps